A dust removal and mist removal device based on wet desulfurization

Abstract

The present invention provides a dust removal and demisting device based on wet desulfurization, which belongs to the field of desulfurization equipment. It includes a desulfurization tower, and the upper part of the desulfurization tower is sequentially provided with a lifting gas cap liquid collection type dust removal and demisting device, a flat tube bundle dust removal and demisting device, and a tube bundle type dust removal and demisting device from bottom to top. The lifting gas cap liquid collection type dust removal and demisting device is provided with a first-stage swirl impeller, and the tube bundle type dust removal and demisting device is provided with a fourth-stage swirl impeller. A first flushing nozzle is provided between the tube bundle type dust removal and demisting device and the flat tube bundle dust removal and demisting device, a second flushing nozzle and a third flushing nozzle are provided between the flat tube bundle dust removal and demisting device and the lifting gas cap liquid collection type dust removal and demisting device, and a fourth flushing nozzle is provided below the lifting gas cap liquid collection type dust removal and demisting device. The lifting gas cap liquid collection type dust removal and demisting device is also connected to a liquid collection discharge pipeline, and the liquid collection discharge pipeline is connected to the outside of the desulfurization tower. Compared with the prior art, the present invention has the characteristics of anti-blocking and strong dust removal and demisting stability, and can perform efficient and continuous dust removal and demisting.

Description

Technical Field

[0001] The present invention belongs to the field of desulfurization equipment, and in particular, relates to a dust and mist removal device based on wet desulfurization. Background Art

[0002] In coal-fired, steel, smelting, coking and other industries, wet flue gas desulfurization devices are equipped with dust collectors and mist eliminators behind the spray layer. In recent years, a large number of tube bundle dust collectors and mist eliminators have been installed. However, the dust removal efficiency of tube bundle dust collectors and mist eliminators is generally around 70%, which is difficult to achieve higher efficiency and meet the ultra-clean emission requirements required by the current environmental protection industry. In addition, the tube bundle dust collector and mist eliminator requires a large amount of flushing water and a frequent flushing frequency. In industries such as steel and smelting where water evaporation is low, insufficient flushing of the dust collector and mist eliminator often leads to blockage, making it difficult to ensure the long-term stable operation of the dust collector and mist eliminator.

[0003] In summary, the existing wet flue gas desulfurization devices have the following main problems in dust removal and demisting, that is, insufficient flushing is prone to occur during the wet flue gas desulfurization process, resulting in blockage of the dust and demisting device during operation, thereby affecting the efficiency of dust removal and demisting of the equipment. In view of this, the present invention provides a dust removal and demisting device based on wet flue gas desulfurization. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a dust removal and demisting device based on wet flue gas desulfurization, which has the characteristics of anti-clogging and strong dust removal and demisting stability, and can perform efficient and continuous dust removal and demisting.

[0005] The present invention is achieved through the following technical solutions:

[0006] A dust removal and demisting device based on wet flue gas desulfurization comprises a desulfurization tower, wherein the upper part of the desulfurization tower is provided with an air-lifting cap liquid-collecting dust-removing and demister, a flat tube bundle dust-removing and demister and a tube bundle dust-removing and demister in sequence from bottom to top, the air-lifting cap liquid-collecting dust-removing and demister is provided with a first-stage swirl impeller, the tube bundle dust-removing and demister is provided with a fourth-stage swirl impeller, a first flushing nozzle is provided between the tube bundle dust-removing and demister and the flat tube bundle dust-removing and demister, a second flushing nozzle and a third flushing nozzle are provided between the flat tube bundle dust-removing and demister and the air-lifting cap liquid-collecting dust-removing and demister, a fourth flushing nozzle is provided below the air-lifting cap liquid-collecting dust-removing and demister, the air-lifting cap liquid-collecting dust-removing and demister is also connected with a liquid collecting discharge pipe, and the liquid collecting discharge pipe is connected to the outside of the desulfurization tower.

[0007] As a preferred technical solution, the first flushing nozzle is connected to a process water pump via a process pipeline, and a first mesh Y-type filter is arranged in the process pipeline.

[0008] As a preferred technical solution, it also includes a circulating clarifying flushing water tank, which is connected to the liquid collecting and discharging pipe through a circulating pipe. A circulating water inlet is also provided in the upper middle part of the circulating clarifying flushing water tank, and the circulating water inlet is connected to the second flushing nozzle, the third flushing nozzle and the fourth flushing nozzle through a flushing pipe. A circulating flushing water pump and a second mesh Y-type filter are provided on the flushing pipe.

[0009] As a preferred technical solution, a mud discharge port is provided at the bottom of the circulating clarifying flushing water tank, and the mud discharge port is connected to the desulfurization tower through a mud discharge pipe, and a mud discharge pump is provided on the mud discharge pipe.

[0010] Beneficial effects:

[0011] The present invention adopts three dust removal and demisting devices which are arranged in sequence from bottom to top, namely, a rising air cap liquid collecting dust removal and demisting device, a flat tube bundle dust removal and demisting device and a tube bundle dust removal and demisting device, so as to achieve multiple dust removal and demisting effects and improve the dust removal and demisting efficiency. In addition, the first flushing nozzle, the second flushing nozzle, the third flushing nozzle and the fourth flushing nozzle can timely flush and backwash the rising air cap liquid collecting dust removal and demisting device, the flat tube bundle dust removal and demisting device and the tube bundle dust removal and demisting device to prevent them from being blocked, thereby ensuring the long-term stable operation of the dust removal and demisting device, and optimizing the pipeline design to avoid excessive flushing water from entering the desulfurization tower, thereby achieving the characteristics of anti-blocking and strong dust removal and demisting stability, and can perform efficient and continuous dust removal and demisting. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of a dust removal and mist removal device based on wet flue gas desulfurization;

[0013] Figure 2 for Figure 1 Diagram of the internal structure of the desulfurization tower.

[0014] Figure ID:

[0015] 1. Lifting cap liquid collecting dust demister; 2. Flat tube bundle dust demister; 3. Tube bundle dust demister; 4. First-stage swirl impeller; 5. First flushing nozzle; 6. Second flushing nozzle; 7. Third flushing nozzle; 8. Fourth flushing nozzle; 9. Liquid collecting discharge pipeline; 10. Process water pump; 11. Process pipeline; 12. First screen Y-type filter; 13. Circulating clarification flushing water tank; 14. Circulating pipeline; 15. Circulating water outlet; 16. Flushing pipeline; 17. Circulating flushing water pump; 18. Second screen Y-type filter; 19. Mud discharge outlet; 20. Mud discharge pump; 100. Desulfurization tower. DETAILED DESCRIPTION

[0016] In order to further explain the technical solution of the present invention, a dust removal and mist removal device based on wet flue gas desulfurization is clearly and completely explained below in conjunction with the accompanying drawings.

[0017] It should be noted that the terms such as "upper", "inner", "middle", "left", "right" and "one" cited in this specification are only for the convenience of description and are not used to limit the scope of implementation of the present invention. Changes or adjustments in their relative relationships, without substantially changing the technical content, should also be regarded as the scope of implementation of the present invention, and it is necessary to make it clear in advance.

[0018] Please refer to the attached Figure 1 and 2 The present invention provides a dust removal and demisting device based on wet desulfurization, comprising a desulfurization tower 100. The desulfurization tower 100 is a conventional wet desulfurization tower 100, which will not be described in detail here. The upper part of the desulfurization tower 100 is provided with a gas-lifting cap liquid-collecting dust-removing and demisting device 1, a flat tube bundle dust-removing and demisting device 2 and a tube bundle dust-removing and demisting device 3 in sequence from bottom to top. The gas-lifting cap liquid-collecting dust-removing and demisting device 1 is provided with a first-stage swirl impeller 4, and the tube bundle dust-removing and demisting device 3 is provided with a fourth-stage swirl impeller (not shown);

[0019] It should be noted that the air-lift cap liquid-collecting dust-removing and mist-removing device 1 is a common air-lift cap in the prior art, and a first-stage swirl impeller 4 is arranged inside the air-lift cap. As the first-stage dust-removing and mist-removing device, it mainly removes slurry droplets with large particle sizes and large dust particles. At the same time, it also serves as a collection device for flushing water of the flat tube bundle dust-removing and mist-removing device 2 and the tube bundle dust-removing and mist-removing device 3 above. The flushing water of the two layers of dust-removing and mist-removing devices is collected outside the tower through the following liquid collection and discharge pipe 9;

[0020] The flat tube bundle dust collector and mist remover 2 is a dust collector and mist remover that has a good removal effect not only on large-size slurry droplets and large-particle dust, but also on small-size slurry droplets and small-particle dust. The flat tube bundle dust collector and mist remover has a short tube length, a simple structure, is easy to flush, and is not easy to clog;

[0021] The tube bundle dust collector and mist remover 3 is an existing tube bundle dust collector and mist remover 3, which has a relatively long tube length and is internally provided with a four-stage swirl impeller (not shown), which has a good effect in removing small-size slurry droplets and small-particle dust, and is the key to ensuring the dust removal and mist removal effect;

[0022] Through the above three-layer dust removal and demisting device, a dust removal effect of more than 85% can be achieved, realizing efficient dust removal and demisting.

[0023] A first flushing nozzle 5 is arranged between the tube bundle dust collector and demister 3 and the flat tube bundle dust collector and demister 2, a second flushing nozzle 6 and a third flushing nozzle 7 are arranged between the flat tube bundle dust collector and demister 2 and the air-lift cap liquid collecting dust collector and demister 1, a fourth flushing nozzle 8 is arranged below the air-lift cap liquid collecting dust collector and demister 1, and the air-lift cap liquid collecting dust collector and demister 1 is also connected to a liquid collecting discharge pipe 9, which is connected to the outside of the desulfurization tower 100.

[0024] Specifically, the first flushing nozzle 5 is connected to a process water pump 10 via a process pipeline 11 , and a first mesh Y-type filter 12 is disposed in the process pipeline 11 .

[0025] Specifically, it also includes a circulating clarifying flushing water pool 13, which is connected to the liquid collecting and discharging pipe 9 through a circulating pipe 14. A circulating water inlet 15 is also provided in the middle and upper part of the circulating clarifying flushing water pool 13. The circulating water inlet 15 is connected to the second flushing nozzle 6, the third flushing nozzle 7 and the fourth flushing nozzle 8 through a flushing pipe 16. A circulating flushing water pump 17 and a second mesh Y-type filter 18 are provided on the flushing pipe 16.

[0026] Specifically, a mud discharge port 19 is provided at the bottom of the circulating clarifying flushing water pool 13 , and the mud discharge port 19 is connected to the desulfurization tower 100 through a mud discharge pipe, and a mud discharge pump 20 is provided on the mud discharge pipe.

[0027] It should be noted that the flushing process is from top to bottom. Since the tube bundle dust collector and mist eliminator 3 has a complex structure and high requirements for flushing, the aperture of the first flushing nozzle 5 is required to be small, generally 1mm to 2mm. Therefore, the process water is used to pressurize the process water pump 10 for flushing. The aperture of the first screen Y-type filter 12 set in the process pipeline 11 is 0.5mm to ensure that the filter will not be blocked. Since the flat tube bundle dust collector and mist eliminator 2 is set below the tube bundle dust collector and mist eliminator 3, the slurry and dust captured by the tube bundle dust collector and mist eliminator 3 are greatly reduced, and a regular time interval can be set for flushing. Generally, the flushing frequency is set to once every four hours.

[0028] After the first flushing nozzle 5 finishes flushing the tube bundle dust collector 3, it falls into the upper surface of the flat tube bundle dust collector 2 for flushing, while the lower surface of the flat tube bundle dust collector 2 is flushed by the second flushing nozzle 6, and the flushing water after flushing falls into the air cap liquid collection type dust collector 1 for collection and discharge; in this embodiment, the flushing water is finally discharged into the circulating clarified flushing water pool 13 through the liquid collection discharge pipe 9, and is recycled by the circulating pipe 14 and the circulating pump, and the aperture of the second flushing nozzle 6 is generally 4mm to 5mm, and the aperture of the second mesh Y-type filter 18 in the circulating pipe 14 is 2mm, so as to ensure that the nozzle will not be blocked, and the flushing frequency is generally set to be once every three hours;

[0029] The lower part of the lifting cap liquid collecting type dust collector and the upper surface of the first-stage swirl impeller 4 are flushed by the fourth flushing nozzle 8 and the third flushing nozzle 7 respectively. The third flushing nozzle 7, the fourth flushing nozzle 8 and the second flushing nozzle 6 share a circulation pipe 14, and the flushing frequency is generally set to once every two hours.

[0030] It should also be noted that the flushing water of the above-mentioned tube bundle dust collector 3 and the flushing water of the horizontal plate tube bundle dust collector 2 will be collected by the air cap liquid collection type dust collector 1, and then enter the circulating clarified flushing water pool 13. This is equivalent to only using the clean process water outside the system to flush the tube bundle dust collector 3; the flushing of the flat tube bundle dust collector 2 and the air cap liquid collection type dust collector 1 uses the clarified water in the system, which saves a lot of water in the system, and the sludge clarified below the circulating clarified flushing water pool 13 is regularly discharged back to the desulfurization tower 100 through the sludge pump.

[0031] The present invention adopts three dust removal and demisting devices, which are arranged from bottom to top in sequence, including a rising air cap liquid collecting dust and demisting device 1, a flat tube bundle dust and demisting device 2 and a tube bundle dust and demisting device 3, to achieve multiple dust removal and demisting effects and improve the dust removal and demisting efficiency. In addition, the first flushing nozzle 5, the second flushing nozzle 6, the third flushing nozzle 7 and the fourth flushing nozzle 8 can timely flush and backwash the rising air cap liquid collecting dust and demisting device 1, the flat tube bundle dust and demisting device 2 and the tube bundle dust and demisting device 3 to prevent them from being blocked, thereby ensuring the long-term stable operation of the dust removal and demisting device, and optimizing the pipeline design to avoid excessive flushing water from entering the desulfurization tower 100, thereby achieving the characteristics of anti-blocking and strong dust removal and demisting stability, and can perform efficient and continuous dust removal and demisting.

[0032] The present invention is not limited to the above-mentioned embodiments. If various modifications or variations of the present invention do not depart from the spirit and scope of the present invention, and if these modifications and variations fall within the scope of the claims of the present invention and equivalent technologies, the present invention also includes these modifications and variations.

Claims

1. A dust removal and mist removal device based on wet desulfurization, comprising a desulfurization tower, characterized in that: The upper part of the desulfurization tower is provided with a gas-lifting cap liquid-collecting dust-eliminator, a flat tube bundle dust-eliminator and a tube bundle dust-eliminator from bottom to top in sequence. The gas-lifting cap liquid-collecting dust-eliminator is provided with a first-stage swirl impeller, the tube bundle dust-eliminator is provided with a fourth-stage swirl impeller, a first flushing nozzle is provided between the tube bundle dust-eliminator and the flat tube bundle dust-eliminator, a second flushing nozzle and a third flushing nozzle are provided between the flat tube bundle dust-eliminator and the gas-lifting cap liquid-collecting dust-eliminator. Nozzle, a fourth flushing nozzle is arranged below the lifting cap liquid collecting dust demister, and the lifting cap liquid collecting dust demister is also connected to a liquid collecting discharge pipe, which is connected to the outside of the desulfurization tower; after the first flushing nozzle completes the flushing of the tube bundle type dust demister, it falls into the upper surface of the flat tube bundle dust demister for flushing, and the lower surface of the flat tube bundle dust demister is flushed by the second flushing nozzle, and the flushing water after flushing falls to the lifting cap liquid collecting dust demister for collection and discharge; The lower part of the lifting cap liquid collection type dust collector and the upper surface of the first-stage swirl impeller are washed by the fourth washing nozzle and the third washing nozzle respectively; the first washing nozzle, the second washing nozzle, the third washing nozzle and the fourth washing nozzle can timely wash and backwash the lifting cap liquid collection type dust and mist collector, the flat tube bundle dust and mist collector and the tube bundle dust and mist collector; The first flushing nozzle is connected to a process water pump through a process pipeline, and a first mesh Y-type filter is arranged in the process pipeline; it also includes a circulating clarifying flushing water tank, the circulating clarifying flushing water tank is connected to the liquid collecting and discharging pipe through a circulating pipe, and a circulating water inlet is also arranged in the middle and upper part of the circulating clarifying flushing water tank, the circulating water inlet is connected to the second flushing nozzle, the third flushing nozzle and the fourth flushing nozzle through a flushing pipe, and a circulating flushing water pump and a second mesh Y-type filter are arranged on the flushing pipe; the flushing water is discharged into the circulating clarifying flushing water tank through the liquid collecting and discharging pipe, and is recycled by the circulating pipe and the circulating pump; The aperture of the first flushing nozzle is 1mm to 2mm, and the aperture of the first mesh Y-type filter is 0.5mm; the aperture of the second flushing nozzle is 4mm to 5mm, and the aperture of the second mesh Y-type filter is 2mm.

2. The dust removal and mist removal device after wet flue gas desulfurization according to claim 1 is characterized in that: A mud discharge port is provided at the bottom of the circulating clarification and flushing water pool, and the mud discharge port is connected to the desulfurization tower through a mud discharge pipeline, and a mud discharge pump is provided on the mud discharge pipeline.

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